Cabazitaxel multiple rechallenges in metastatic castration-resistant prostate cancer

Abstract

Introduction: Cabazitaxel multiple rechallenges may be a treatment option in heavily pretreated patients with metastatic castration-resistant prostate cancer (mCRPC) who had a good initial response to cabazitaxel and who are still fit to receive it. Our objective was to assess the efficacy and toxicity of multiple rechallenges.

Patients and methods: We retrospectively identified 22 mCRPC patients previously treated with docetaxel and/or androgen receptor-targeted agents who received multiple cabazitaxel rechallenges in 9 French centers. Cabazitaxel was initiated at a dose of 25 mg/m² q3week. A reduced dose (20 mg/m² q3w) or an alternative schedule (mainly 16 mg/m² q2w) was increasingly used for subsequent rechallenges. Progression-free survival, prostate-specific antigen (PSA) response, best clinical response, and grade ≥3 toxicities were collected. Overall survival was calculated from various time points.

Results: Twenty-two patients with an initial response to cabazitaxel were rechallenged at least twice. The median number of cabazitaxel cycles was 7 at first cabazitaxel treatment, 6 at first rechallenge, and 5 at subsequent rechallenges. Median progression-free survival at first rechallenge was 9.6 months and 5.6 months at second rechallenge. Median overall survival was 50.9 months from the first cabazitaxel dose, 114.9 months from first life-extending therapy initiation in mCRPC, and 105 months from mCRPC diagnosis. There was no cumulative grade ≥3 neuropathy or nail disorder and one case of febrile neutropenia.

Conclusion: Cabazitaxel multiple rechallenges may be a treatment option without cumulative toxicity in heavily pretreated patients having a good response to first cabazitaxel use and still fit to receive it.

Novelty & impact statements: Patients with metastatic castration-resistant prostate cancer can be treated with Cabazitaxel after docetaxel and androgen receptor-targeted agent. This chemotherapy can be used multiple times with efficacy and manageable toxicity.

Keywords: cancer management; chemotherapy; metastasis; prostate cancer; urological oncology.